Quality-assurance study of marine lipid-class determination using chromarod/iatroscan® thin-layer chromatography-flame ionization detector

• Published in: Environmental toxicology and chemistry 2000-09, Vol.19 (9), p.2189-2197
• Main Authors: Bergen, Barbara J., Quinn, James G., Parrish, Christopher C.
• Format: Article
• Language: English
• Subjects: Animal, plant and microbial ecology; Applied ecology; Biological and medical sciences; Chromatography; Ecotoxicology, biological effects of pollution; Fundamental and applied biological sciences. Psychology; Iatroscan; Ionization detector; Marine lipids; Quality assurance; Techniques
• ISSN: 0730-7268; 1552-8618
• DOI: 10.1002/etc.5620190907

An Iatroscan® thin‐layer chromatography–flame ionization detector has been utilized to quantify lipid classes in marine samples. This method was evaluated relative to established quality‐assurance (QA) procedures used for the gas chromatographic analysis of PCBs. A method for extracting and analyzing eight major lipid classes in the ribbed mussel (Guekensia demissus) was developed. The analytical method met the QA criteria prescribed for consistent external calibrations, low blanks, complete extraction of all lipid classes, and precise replicate analysis. Matrix and blank spikes were satisfactorily recovered (50‐130%), provided that the samples contained a large enough mass (>4% dry weight) of total lipids to overcome the absorption of polar lipids on glassware. The use of frozen mussel homogenate as a standard reference material was not possible because of lipid degradation, particularly of triacylglycerols and phospholipids. Also, total lipids measured gravimetrically significantly decreased in frozen samples, which could influence bioaccumulation predictions. A laboratory intercalibration was performed using a mussel homogenate and chloroform extract, which verified the accuracy of the method and the lipid‐class identification. Characterizing the structure of one class of polar lipids, the acetone mobile polar lipid (AMPL), showed that it contained no ester linkages or free/sterically unhindered ‐OH groups; however, the AMPL did contain an ether linkage.